The current behavior, for example in gucharmap, is:

- I open the "search" dialog and enter some string
- I move the mouse cursor on the "next" button.
- I click on the "next" button.
- The button flickers a bit, as it is disabled and enabled again.
- I click on the "next" button again. The button gets a dotted frame, but its action is not executed, that is, the search doesn't continue.
- I move the mouse cursor out of the button and into it again.
- I click on the button, and it behaves as intended.

So when the mouse cursor is already over the button at the point where it is enabled, you cannot directly click on it but have to move the mouse cursor. That's inconvenient.

Other information: